This invention relates generally to current sources and, in particular, to devices for displaying the output and status of current sources.
Electrosurgical generators are used by surgeons to deliver electrical energy used, for example, in electrosurgical techniques such as tissue cutting, coagulating small blood vessels, vessel sealing and tissue welding. Radio frequency (RF) power is produced by the electrosurgical generator and applied to the tissue through an electrosurgical tool. RF current is applied utilizing two methods: monopolar, where power is applied to the tissue through a small active electrode and returned through the patient""s body to a large return electrode; or bipolar, where power is applied and returned through two small electrodes usually spaced less than a millimeter apart.
Electrosurgical tissue cutting is accomplished by applying an amount of RF current between two electrodes sufficient enough to destroy the tissue. This causes a controlled path of tissue destruction along the electrical path between the electrodes.
The coagulation of small blood vessels is accomplished by applying an amount of RF current which desiccates the tissue to a point where the tissue cells are ruptured and dried but not significantly charred. An application of this technique includes closing small vascular vessels.
Vessel sealing and tissue welding are accomplished by using a suitable electrosurgical tool to grasp and clamp together opposing sides of the wall of a vessel, or two layers of tissue. The opposing sides or two layers are then welded together by applying a controlled amount of RF current, causing a desiccation process where the collagen in the layers of tissue is liquefied so that it cross links between the layers and reforms into a fused mass with a minimum amount of tissue destruction.
It should be noted that each of these techniques requires different amounts and durations of applied RF current. Because these techniques are ultimately dependant on the quantity of RF power applied, in order to achieve successful clinical results during surgery, and to avoid any undesirable tissue damage, it is important that the surgical team should be provided with an indication of the amount of RF current being applied during electrosurgical procedures.
Many electrosurgical generators include various indicators on a front panel. Some have built in current measurement displays. However, electrosurgical generators are normally intended to be small so as not to occupy a large amount of space in the operating room. This results in the indications of the operating status of the generator on the front panel being correspondingly small, and thus potentially not readily visible to all interested members of the surgical team. Also, the electrosurgical generator is usually placed in close proximity to the patient and the surgeon to minimize the length of the electrical connection between the electrosurgical generator and the electrosurgical instruments. This may also result in blocking the indicators from view due to the placement of the operating table, other operating room personnel, etc.
It can be appreciated that it would be desirable to provide a visual and audible indication, external to the electrosurgical generator. An indication of the operational status and the current being generated by the electrosurgical generator, observable by the surgical team, would be beneficial. Also desirable would be an overall indication of the status of the external device providing the indications.
The forgoing and other problems are overcome by methods and apparatus in accordance with embodiments disclosed herein.
A remote monitor provides a visual indication of the RF current being delivered by an electrosurgical generator. The monitor optionally further provides an audible indication of the RF current being delivered and a means to control the volume of the audible indication, mute the audible indication, and to visually indicate that the audible indicator is muted. The monitor further provides additional visual indications corresponding to the operational status of the electrosurgical generator, and the operational status of the monitor""s internal control circuitry. The monitor still further provides the visual and audible indications remote from the electrosurgical generator and provides them in such a way that the visual and audible indications can be readily observed and heard within an area normally associated with a working area of a typical operating room.